Integral Calculus By Das And Mukherjee Pdf -

3️⃣ PARTIAL FRACTIONS • Proper rational function required. • Factor denominator completely. • Write A/(x‑a)+B/(x‑b)… (linear) or (Cx+D)/(quadratic) (irreducible). • Solve for constants (equate coefficients or plug‑in).

7️⃣ QUICK CHECKLIST BEFORE FINISHING • Did I revert u→x (if indefinite)? • Did I adjust limits (if definite)? • Is the result simplified? (Combine logs, rationalize) • Add constant C for indefinite integrals. integral calculus by das and mukherjee pdf

2️⃣ INTEGRATION BY PARTS • Formula: ∫u dv = uv – ∫v du • Choose u = “algebraic” (poly, log) → du simpler. • dv = “trig, exp, power” → v easy. • Solve for constants (equate coefficients or plug‑in)

------------------------------------------------- CHAPTER 3 – TECHNIQUES OF INTEGRATION ------------------------------------------------- 1️⃣ SUBSTITUTION • Look for f(g(x))·g'(x) pattern. • Set u = g(x) → du = g'(x)dx. • Replace limits if it’s a definite integral. • Is the result simplified

6️⃣ COMMON INTEGRALS (keep this table) ∫dx/(x²+a²) = (1/a) arctan(x/a)+C ∫dx/(x²–a²) = (1/2a) ln| (x‑a)/(x+a) |+C ∫dx/√(a²‑x²) = arcsin(x/a)+C ∫dx/√(x²‑a²) = ln|x+√(x²‑a²)|+C

4️⃣ TRIG INTEGRALS • Powers of sin/cos: - If odd power of sin → u = cos. - If odd power of cos → u = sin. • Both even → use identities: sin²x = (1‑cos2x)/2, cos²x = (1+cos2x)/2 • Products sin·cos → use substitution u = sin or cos.

5️⃣ TRIG SUBSTITUTIONS • √(a²–x²) → x = a sinθ • √(a²+x²) → x = a tanθ • √(x²–a²) → x = a secθ • Remember dx and simplify.